package com.java.program_questions;

import java.util.Scanner;

/**
 * 问题：编写一个函数，输入n为偶数时，调用函数求1/2+1/4+...+1/n；当输入n为奇数时，调用函数1/1+1/3+...+1/n
 * 分析：
 */
public class Question39 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.print("请输入一个数：");
        int number = sc.nextInt();

        if (number % 2 == 0) { //偶
            double number1 = ou(number);
            System.out.print(number1);
        } else { //奇
            double number1 = ji(number);
            System.out.print(number1);
        }
    }

    public static double ou(int n) {
        int i = 2;
        double count = 0.0;
        while (i <= n) {
            count += 1.0 / i;
            i += 2;
        }
        return count;
    }

    public static double ji(int n) {
        int i = 1;
        double count = 0.0;
        while (i <= n) {
            count += 1.0 / i;
            i += 2;
        }
        return count;
    }
}
